Protecting SQL Server availibility groups with legacy policies

You can use legacy policies to protect an AG environment in the following ways:

With a policy that protects the preferred replica.
With a policy that protects a specific node in the AG.
If an AG crosses multiple NetBackup domains, you can use Auto Image Replication (A.I.R.) to replicate the backup to the other NetBackup domains.
See Configuring SQL Server backups when an availability group crosses NetBackup domains.
NetBackup supports backups of AGs in multi-NIC environments. For more information, see the following topic:
See About configuration of SQL Server backups with multiple NICs.